An electronic device provides a user with at least one user perceivable output quantity, which may be visible, audible or tactile. For example, volume control may change an audible output quantity, i.e. the amplification of voice or sound may increase or decrease.
The volume control of an audible quantity may be performed using a button, a joystick, a mouse or determined keys in the keyboard.
Fingerprint sensors may also be used for controlling the audible output quantity of the electronic device. There is a plurality of sensor types for detecting a fingerprint. The sensors may comprise an array or a matrix of pixels as a detector in order to form a digital image of the fingerprint. The fingerprint sensors may form an image of a fingertip by, for example, an optical measurement, a thermal measurement, a capacitance measurement, an electric field measurement, a conductance measurement or a pressure measurement.
Volume of sound or voice of the electronic device may be made louder or quieter by a linear movement of a finger over the fingerprint sensor. The linear movement can be a direct up or down motion of a finger over the sensor. For instance, an upward motion of a finger may mean a louder volume and a downward movement of a finger may mean that the volume is to be turned down.
There are, however, problems related to these kinds of controls of the user perceivable output quantity. As the electronic devices are getting smaller and smaller, a separate interface, like a button, a joystick, a mouse or a keyboard, is not desirable. Additionally, moving parts wear and make interfaces unreliable. Sweeping a finger over the sensor, in turn, is not always user friendly and easily usable.